<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <!-- 元素选择器 -->

    <style>

            div{
                color: red;
                background-color: yellow;
            }
            h1{
                color: blue;
            }

    </style>

</head>
<body>
    

<div>1111111111111111111111</div>
<div>22222222222222222222222</div>
<h1>eeeeeeeeeeeeeeeeeeeeeeeee</h1>
<h2>rrrrrrrrrrrrrrrrrrrrrrrrr</h2>
</body>
</html>